what carb is on it?
What year car?
sounds like its running damn rich to me, fouling plugs and such. But when you rev it up it gets enough air to clear out and start firing the other three cylinders.
EDIT: you said its a 1970, but then said you suspect a faulty ignition control module. I thought electronic ignition didnt come on cars until 73?.
correct me if i'm wrong.
and also, pictures please
